To calculate setting and drift you need ______.

To calculate setting and drift you need ______.

• A. An Electronic Fix in a Dead Reckoning Position
• B. A Star Fix
• C. A Radar Range to a Known Object
• D. A Range to Land

Answer: (A)

Setting and drift come from comparing where you actually are with where your dead reckoning (DR) says you are. An electronic fix provides your real position, which you compare to the DR position to see how far off you are and in what direction. The direction from the DR position to the actual fix gives the setting (the current’s direction), and the rate at which that cross-track error grows gives the drift (the current’s speed). Other options don’t reliably give you a usable position fix tied to your DR, or they lack the bearing information needed to determine the current’s direction, so they don’t directly yield setting and drift.

Setting and drift come from comparing where you actually are with where your dead reckoning (DR) says you are. An electronic fix provides your real position, which you compare to the DR position to see how far off you are and in what direction. The direction from the DR position to the actual fix gives the setting (the current’s direction), and the rate at which that cross-track error grows gives the drift (the current’s speed). Other options don’t reliably give you a usable position fix tied to your DR, or they lack the bearing information needed to determine the current’s direction, so they don’t directly yield setting and drift.